CORALS FROM THE MOUNTAIN LIMESTONE. 157 



Corattum forming a thin incrustating expansion, its upper surface almost horizontal. 

 Calices polygonal, very deep, rather unequal in size, and separated by slightly exsert 

 ridges. Septal stria 40 or 50 in number, almost equally developed, subvermiculate, and 

 extending on the tabulae to a small distance from the walls. Tabula closely set, almost 

 horizontal towards the centre of the corallites, but very irregular towards their circum- 

 ference. Diagonal of the calices from 5 to 8 lines. 



Found at Hook-point, in Ireland, by Professor M'Coy ; and at Tournay, in Belgium. 



We have not been enabled to study any British specimens of this species ; those that 

 we have examined belonged to the carboniferous formation of Belgium; but the figure 

 published by Professor M'Coy is sufficient to establish the specific identity between the 

 Continental and the Irish fossil here alluded to ; and we feel, consequently, no hesitation 

 in inscribing M. antiqua in the list of British Corals. 



In this species, as well as in M. geometrica} and in M. concinna 2 , there are very 

 numerous, almost horizontal, tabulae; a structural peculiarity, which sufficiently dis- 

 tinguishes them from M. favosa? M. tenuisepta, 4, M. megastoma, 5 and M. convexa? in 

 which the endotheca is entirely vesicular. M. antiqua differs from M. geometrica by the 

 irregularity of its calices, the prolongation of the septal striae on the upper surface of the 

 tabulae ; the latter character, and its large size, also distinguishes it from M. concinna. 



3. Genus Alveolites, (p. lx.) 

 1. Alveolites septosa. Tab. XLV, figs. 5, 5«, bb. 



Favosites septosus, Fleming, Brit. Anim., p. 529, 1828. 



— — 8. Woodward, Syn. Table of Brit. Org. Rem., p. 5, 1830. 



— — Phillips, Geol. of Yorkshire, 2d part, p. 200, pi. ii, figs. 6, 7, 8, 1836. 



— — M'Coy, Syn. Carb. Foss. of Ireland, p. 192, 1844. 

 CHyETETES septosus, Keyserliny, Reise in Petscbora, p. 183, 1846. 



Alveolites septosa, Milne Edwards and Jules Haime, Pol. Foss. desTerr. Palseoz., p. 259, 



1851. 

 Ciletetes septosus, M'Coy, Brit. Palseoz. Foss., p. 82, 1851. 



Corallum forming an incrustating, slightly convex, or subgibbose mass, which is in 

 general composed of superposed strata. Calices unequally developed, somewhat irregular 

 in form, but in general polygonal and not having a prominent edge. Walls rather thin. 

 The solitary septal process well characterised, and sometimes facing two small denticula. 

 Breadth of the calices half a line or a little more. 



1 Milne Edwards and Jules Haime, Polyp. Palseoz., tab. xvii, fig. 3. 



2 Lonsdale, in Murch., Vern., and Keyser., Geology of Russia, vol. i, p. 611, pi. a, fig. 3. 



3 See tab. xliv, fig. 2. * See tab. xliv, fig. 1. 5 See tab. xliv, fig. 3. 



6 D'Orbigny, Prod., vol. i, p. 107 ; Milne Edwards and J. Haime, op. cit., p. 251, tab. xvi, fig. 1. 



